Abstract
The caudal part of the spinal cord is formed by a process called secondary neurulation Secondary neurulation. Secondary neurulation begins with the formation of the medullary cord Medullary cord from pluripotent cells at the area of the primitive streak, followed by intramedullary vacuole formation and canalization, and, finally, retrogressive differentiation of the medullary cord. Thickened filum terminale Filum terminale is a common secondary neurulation defect resulting from partial regression arrest at the late stage of secondary neurulation. It may or may not cause neurological deficits. Retained medullary cord, which is rare, presumably results from a more severe and complete form of regression arrest during late secondary neurulation and is much more likely to cause injury to the conus. Both entities are discussed in light of our present knowledge of secondary neurulation.
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Pang, D., Chong, S., Wang, KC. (2020). Secondary Neurulation Defects-1: Thickened Filum Terminale, Retained Medullary Cord. In: Di Rocco, C., Pang, D., Rutka, J. (eds) Textbook of Pediatric Neurosurgery. Springer, Cham. https://doi.org/10.1007/978-3-319-72168-2_112
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DOI: https://doi.org/10.1007/978-3-319-72168-2_112
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